fprintf(file, "name:%s ,age:%d, id:%d\n", students[0].name, students[0].age, students[0].studentID);
        fprintf(file, "name:%s ,age:%d, id:%d\n", students[1].name, students[1].age, students[1].studentID);
        fprintf(file, "name:%s ,age:%d, id:%d\n", students[2].name, students[2].age, students[2].studentID);